Auto Detecting and Auto Switching Antennas in a Mutli-Antenna FM Transmit/Receive System

ABSTRACT

Methods and systems for auto detecting and auto switching antennas in a multi-antenna FM transmit/receive system are disclosed and may include electronically detecting when an external antenna may be coupled to an external port of the wireless device and utilizing the external antenna for transmitting and/or receiving FM signals. The decoupling of an external antenna from an external port may be detected, which may cause the FM radio transmitter/receiver to be configured to transmit and/or receive FM signals utilizing antennas internal to the wireless device. One or more test signals, which may include AC signals, may be generated within the chip for detecting whether an external antenna may be coupled to an external port. A reflected signal from an external port may be measured and compared to a prestored value corresponding to a reflection due to an open circuit at the one or more external ports of the wireless device.

CROSS-REFERENCE TO RELATED APPLICATIONS/INCORPORATION BY REFERENCE

This application makes reference to and claims priority to U.S.Provisional Application Ser. No. 60/895,665, filed on Mar. 19, 2007,which is hereby incorporated herein by reference in its entirety.

This application makes reference to:

U.S. patent application Ser. No. ______ (Attorney Docket Number18568U502) filed on even date herewith;U.S. patent application Ser. No. ______ (Attorney Docket Number18569U502) filed on even date herewith;U.S. patent application Ser. No. ______ (Attorney Docket Number18570U502) filed on even date herewith; andU.S. patent application Ser. No. ______ (Attorney Docket Number18571U502) filed on even date herewith.

Each of the above stated applications is hereby incorporated herein byreference in its entirety.

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[Not Applicable]

MICROFICHE/COPYRIGHT REFERENCE

[Not Applicable]

FIELD OF THE INVENTION

Certain embodiments of the invention relate to wireless communication.More specifically, certain embodiments of the invention relate to amethod and system for auto detecting and auto switching antennas in amulti-antenna FM transmit/receive system.

BACKGROUND OF THE INVENTION

With the increasing popularity of various wireless standards andtechnologies, there is a growing demand to provide a simple and completesolution for wireless communications applications. Some wirelesscommunication devices utilize a plurality of wireless technologies andmay require separate processing hardware and/or separate processingsoftware. Moreover, coordinating the reception and/or transmission ofdata to and/or from the portable electronic device may requiresignificant processing overhead that may impose certain operationrestrictions and/or design challenges. For example, Bluetooth andWireless LAN may pose certain coexistence problems caused by the closeproximity of the Bluetooth and WLAN transceivers.

Furthermore, simultaneous use of a plurality of radios in a handheldcommunication device may result in significant increases in powerconsumption. Power being a precious commodity in most wireless mobiledevices, devices that utilize a plurality of wireless technologiesrequire careful design and implementation in order to minimize batteryusage. Accordingly, the transmission of these multiple wireless protocolsignals may require novel transmitter and receiver designs to sharecomponents within the device and optimize power usage.

Further limitations and disadvantages of conventional and traditionalapproaches will become apparent to one of skill in the art, throughcomparison of such systems with the present invention as set forth inthe remainder of the present application with reference to the drawings.

BRIEF SUMMARY OF THE INVENTION

A system and/or method for auto detecting and auto switching antennas ina multi-antenna FM transmit/receive system, substantially as shown inand/or described in connection with at least one of the figures, as setforth more completely in the claims.

Various advantages, aspects and novel features of the present invention,as well as details of an illustrated embodiment thereof, will be morefully understood from the following description and drawings.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

FIG. 1A is a block diagram of an exemplary system that enablesmulti-protocol communication, in accordance with an embodiment of theinvention.

FIG. 1B is a block diagram of an exemplary FM transmitter thatcommunicates with handheld devices that utilize a single chip with anintegrated FM transmitter and receiver, in accordance with an embodimentof the invention.

FIG. 1C is a block diagram of an exemplary FM receiver that communicateswith handheld devices that utilize a single chip with an integrated FMtransmitter and FM receiver in accordance with an embodiment of theinvention.

FIG. 2 is a block diagram of an exemplary system for FM transmission andreception, in accordance with an embodiment of the invention.

FIG. 3 is a block diagram illustrating an exemplary wireless deviceincorporating automatic antenna sensing and switching, in accordancewith an embodiment of the invention.

FIG. 4 is a block diagram illustrating an exemplary wireless deviceantenna sensing system, in accordance with an embodiment of theinvention.

FIG. 5 is a block diagram illustrating an alternative embodiment of anexternal antenna sensing system, in accordance with an embodiment of theinvention.

FIG. 6 is a flow diagram illustrating an exemplary external antennasensing process, in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Certain aspects of the invention may be found in a method and system forauto detecting and auto switching antennas in a multi-antenna FMtransmit/receive system. Exemplary aspects of the invention may comprisedetecting whether an external antenna may be coupled to one or moreexternal port of the wireless device. The wireless device may comprise aportable or mobile wireless end user communication device. FM signalsmay be transmitted and/or received via the FM radio transmitter and/orFM radio receiver respectively, in instances when the external antennamay be detected. The FM radio transmitter may be configured fortransmitting the FM signal via the external antenna when the externalantenna may be detected, and the FM radio receiver may be configured forreceiving the FM signals via the external antenna when the externalantenna may be detected. In instances when the one or more externalantennas may be decoupled from one or more of the external ports, suchdecoupling may be detected. The FM radio transmitter and FM radioreceiver may be configured to transmit and/or receive the FM signal,respectively, utilizing antennas internal to the wireless device whenthe decoupling of the one or more external antennas may be detected. Oneor more test signals may be generated within the chip for detectingwhether the external antenna may be coupled to the one or more externalports of the wireless device. A reflected signal resulting from areflection of the generated one or more test signals when the generatedtest signal may be communicated to the one or more external ports of thewireless device may be measured and compared to a prestored valuecorresponding to a reflection due to an open circuit at the one or moreexternal ports of the wireless device. The AC test signal may comprisean AC signal.

FIG. 1A is a block diagram of an exemplary system that enablesmulti-protocol communication, in accordance with an embodiment of theinvention. Referring to FIG. 1A, there is shown a mobile terminal 150comprising a plurality of transceivers 151, 152, and 153, a basebandprocessor 154, a processor 156, external antennas 160 a-f, internalantennas 162 a-c and system memory 158. The transceivers 151, 152, and153 may each comprise a transmitter front end 151 a, 152 a, 153 a,respectively, and a receiver front end 151 b, 152 b, 153 b,respectively.

The transmitter front ends 151 a, 152 a, and 153 a may comprise suitablecircuitry, logic, and/or code that may be adapted to process andtransmit RF signals. In an embodiment of the invention, the transmitterand receiver front ends for each wireless protocol may be integrated ona single chip. In another embodiment of the invention, each of thetransceivers may be integrated on a single chip.

The external antennas 160 a-f and the internal antennas 162 a-c maycomprise antennas that may be used for different wireless protocols,such as Bluetooth, NFC, WLAN and FM, for example. The external antennasmay be attached or detached from the wireless device 150, and maycomprise components that may be used for purposes other than actingsolely as antennas, such as speakers or earphones, for example. Theinternal antennas 162 a-c may each comprise any metal component withinthe wireless communication device that may act as an antenna. One ormore of the antennas may be selected to transmit and/or receive wirelesssignals. In an embodiment of the invention, a plurality of combinationsof selected antennas may be switched on, and received signals may bemeasured and compared to assess the optimum antenna configuration at aparticular frequency.

The transmitter front ends 151 a, 152 a, and 153 a may receive basebandsignals communicated by a baseband processor, such as, for example, thebaseband processor 154. The signals may then be, for example, filtered,amplified, upconverted, and/or modulated for transmission. The basebandsignal may be analog or digital depending on the functionality of thetransmitter front end 151 a, 152 a, or 153 a and the baseband processor154.

The receiver front ends 151 b, 152 b, and 153 b may comprise suitablecircuitry, logic, and/or code that may be adapted to receive and processRF signals. The receiver front ends 151 b, 152 b, and 153 b may amplify,filter, down-convert, and/or demodulate the received signals to generatea baseband signal. The baseband signal may be analog or digitaldepending on the functionality of the receiver front end 151 b, 152 b,or 153 b and the baseband processor 154.

The baseband processor 154 is depicted as a single block for the sake ofsimplicity, however, the invention need not be so limited. For example,other embodiments of the invention may comprise a plurality of basebandprocessors for processing signals to and/or from the transceivers 151,152, and 153.

The baseband processor 154 may comprise suitable circuitry, logic,and/or code that may be adapted to process received baseband signalsfrom the receiver front ends 151 b, 152 b, and 153 b. The basebandprocessor 154 also may comprise suitable logic, circuitry, and/or codethat may be adapted to process a baseband signal for communication tothe transmitter front ends 151 a, 152 a, and 153 a.

The processor 156 may comprise suitable logic, circuitry, and/or codethat may be adapted to control the operations of the transceivers 151,152, and 153 and/or the baseband processor 154. For example, theprocessor 156 may be utilized to update and/or modify programmableparameters and/or values in a plurality of components, devices, and/orprocessing elements in the transceivers 151, 152, and 153 and/or thebaseband processor 154. Control and/or data information may also betransferred to and/or from another controller and/or processor in themobile terminal 150 to the processor 156. Similarly, the processor 156may transfer control and/or data information to another controllerand/or processor in the mobile terminal 150.

In operation, the processor 156 may utilize the received control and/ordata information to determine a mode of operation for the transceivers151, 152, and/or 153. For example, the processor 156 may control each ofthe receiver front ends 151 b, 152 b, and 153 b to receive RF signals ata specific frequency. Similarly, the processor 156 may control each ofthe transmitter front ends 151 a, 152 a, and 153 a to transmit RFsignals at a specific frequency. The processor 156 may also adjust aspecific gain for a variable gain amplifier, and/or adjust filteringcharacteristics for a filter. Moreover, a specific frequency selectedand/or parameters needed to calculate the specific frequency, and/or thespecific gain value and/or the parameters needed to calculate thespecific gain, may be stored in the system memory 158 via the processor156. This information stored in system memory 158 may be transferred tothe receiver front end 152 from the system memory 158 via the processor156. The system memory 158 may comprise suitable circuitry, logic,and/or code that may be adapted to store a plurality of control and/ordata information, including parameters needed to calculate frequenciesand/or gain, and/or the frequency value and/or gain value.

The wireless protocols transmitted and received by the mobile terminal150 may comprise FM, WLAN, Bluetooth and near field communication (NFC),for example. Antenna design may be more challenging for the transmissionand reception of FM signals, as the wavelength becomes larger whencompared to the size of the wireless device 150. External devices, suchas earphones, for example, that may be plugged into a port of thewireless device 150 may improve FM reception. Thus, the ability toautomatically detect when an external device is coupled to a port on thewireless device 150 that may be used to receive FM signals may improvereception.

FIG. 1B is a block diagram of an exemplary FM transmitter thatcommunicates with handheld devices that utilize a single chip with anintegrated FM transmitter and receiver, in accordance with an embodimentof the invention. Referring to FIG. 1B, there is shown an FM transmitter102, a cellular phone 104 a, a smart phone 104 b, a computer 104 c, andan exemplary multi-wireless protocol equipped device 104 d. The FMtransmitter 102 may be implemented as part of a radio station or otherbroadcasting device, for example. Each of the cellular phone 104 a, thesmart phone 104 b, the computer 104 c, and the exemplary multi-wirelessprotocol equipped device 104 d may comprise a single chip 106 a, 106 b,106 c and 106 d with an integrated FM transmitter and receiver. The FMtransmitter 102 may enable communication of FM audio data to the devicesshown in FIG. 1B by utilizing the single chip 106 a, 106 b, 106 c and106 d in each device. Each of the devices in FIG. 1B may comprise and/ormay be communicatively coupled to a listening device 108 such as aspeaker, a headset, or an earphone, for example.

The cellular phone 104 a may be enabled to receive an FM transmissionsignal from the FM transmitter 102. The user of the cellular phone 104 amay then listen to the transmission via the listening device 108. Thecellular phone 104 a may comprise a “one-touch” programming feature thatenables pulling up specifically desired broadcasts, like weather,sports, stock quotes, or news, for example. The smart phone 104 b may beenabled to receive an FM transmission signal from the FM transmitter102. The user of the smart phone 104 b may then listen to thetransmission via the listening device 108.

The computer 104 c may be a desktop, laptop, notebook, tablet, and/or aPDA, for example. The computer 104 c may be enabled to receive an FMtransmission signal from the FM transmitter 102. The user of thecomputer 104 c may then listen to the transmission via the listeningdevice 108. The computer 104 c may comprise software menus thatconfigure listening options and enable quick access to favorite options,for example. In one embodiment of the invention, the computer 104 c mayutilize an atomic clock FM signal for precise timing applications, suchas scientific applications, for example. While a cellular phone, a smartphone, computing devices, and other devices are shown in FIG. 1B, thesingle chip 106 may be utilized in a plurality of other devices and/orsystems that receive and use multiple wireless protocols such asBluetooth, NFC, WLAN, RFID and FM signals, for example.

For each wireless device 104 a-d, the listening device 108 may also actas antenna for the reception of FM signals due to its larger size ascompared to built-in antennas internal to the wireless devices. Thelistening device may be connected or disconnected at any time, testingfor the presence of an externally coupled device, such as the listeningdevice 108, may be performed at regular intervals. In another embodimentof the invention, the wireless device may sense externally coupleddevices continually.

FIG. 1C is a block diagram of an exemplary FM receiver that communicateswith handheld devices that utilize a single chip with an integrated FMtransmitter and FM receiver in accordance with an embodiment of theinvention. Referring to FIG. 1C, there is shown an FM receiver 110, thecellular phone 104 a, the smart phone 104 b, the computer 104 c, and theexemplary multi-wireless protocol equipped device 104 d. In this regard,the FM receiver 110 may comprise and/or may be communicatively coupledto a listening device 108. A device equipped with an integrated FMtransmitter and FM receiver, such as the single chip 106 a, 106 b, 106 cor 106 d, may be able to transmit or broadcast its respective signal toa “deadband” of an FM receiver for use by the associated audio system.For example, a cellphone or a smart phone, such as the cellular phone104 a and the smart phone 104 b, may transmit a telephone call forlistening over the audio system of an automobile, which may comprise theFM receiver 110 and the speakers 108, via usage of a deadband area ofthe car's FM stereo system. This may provide a universal capability touse this feature with all automobiles equipped simply with an FM radiowith few, if any, other external FM transmission devices or connectionsbeing required.

In another example, a computer, such as the computer 104 c, may comprisean MP3 player or another digital music format player and may broadcast asignal to the deadband of the FM receiver 110 which may be part of ahome stereo system. The music on the computer 104 c may then be listenedto on a standard FM receiver such as the FM receiver 110, with few, ifany, other external FM transmission devices or connections. While acellular phone 104 a, a smart phone 104 b, and computing device 106 care shown, a single chip that combines an FM transmitter and an FMreceiver may be utilized in a plurality of other devices and/or systemsthat receive and use an FM signal.

For each wireless device 104 a-d, the listening device 108 may also actas antenna for the transmission of FM signals due to its larger size ascompared to built-in antennas internal to the wireless devices. Thelistening device 108 may be connected or disconnected at any time, sotesting for the presence of an externally coupled device, such as thelistening device 108, may be performed at regular intervals. In anotherembodiment of the invention, the wireless device may sense externallycoupled devices continually.

FIG. 1D is a block diagram of an exemplary single chip with integratedBluetooth and FM radio Tx and FM radio Rx that supports FM processingand an external device that supports Bluetooth processing, in accordancewith an embodiment of the invention. Referring to FIG. 1D, there isshown a single chip 112 a that supports Bluetooth and FM radio Tx and FMradio Rx operations and an external device 114. The single chip 112 amay comprise an integrated Bluetooth radio 116, an integrated FM radioRx 118, an integrated processor 120, a coupler 123 and an FM transmitter(Tx) 121. The Bluetooth radio 116 may comprise suitable logic,circuitry, and/or code that enable Bluetooth signal communication viathe single chip 112 a. In this regard, the Bluetooth radio 116 maysupport processing, playback and communication of audio signals. The FMradio Rx 118 may comprise suitable logic, circuitry, and/or code thatenable reception of FM signals via the single chip 112 a.

The integrated processor 120 may comprise suitable logic, circuitry,and/or code that may enable processing of the FM data received by the FMradio Rx 118. Moreover, the integrated processor 120 may enableprocessing of FM data to be transmitted by the FM radio Tx 121. Theexternal device 114 may comprise a baseband processor 122. The basebandprocessor 122 may comprise suitable logic, circuitry, and/or code thatmay enable processing of Bluetooth data received by the Bluetooth radio116. Moreover, the baseband processor 122 may enable processing ofBluetooth data to be transmitted by the Bluetooth radio 116. In thisregard, the Bluetooth radio 116 may communicate with the basebandprocessor 122 via the external device 114. The Bluetooth radio 116 maycommunicate with the integrated processor 120. The FM radio Tx 121 maycomprise suitable logic, circuitry, and/or logic that may enabletransmission of FM signals via appropriate broadcast channels, forexample.

The coupler 123 may comprise suitable circuitry, logic and/or code forcoupling the Rx and Tx antennas, or external antennas coupled to theexternal ports, to the FM radio Rx 118 and the FM radio Tx 121. In thismanner, each, or both antennae may be utilized to transmit and/orreceive FM signals. A maximum transmit and/or received signal may beobtained if a suitable external antenna is coupled to the single chip112 a.

FIG. 1E is a block diagram of an exemplary single chip with integratedBluetooth and FM radios and an external device that supports Bluetoothand FM processing, in accordance with an embodiment of the invention.Referring to FIG. 1D, there is shown a single chip 112 b that supportsBluetooth and FM radio operations and an external device 114. The singlechip 112 b may comprise the Bluetooth radio 116, an FM radio Rx 118, acoupler 123 and an FM radio Tx 121. The Bluetooth radio 116 and/or theFM radio Rx 118 and FM radio Tx 121 may be integrated into the singlechip 112 b. The external device 114 may comprise a baseband processor122.

The baseband processor 122 may comprise suitable logic, circuitry,and/or code that may enable processing of Bluetooth data received by theBluetooth radio 116 and/or processing of Bluetooth data to betransmitted by the Bluetooth radio 116. In this regard, the Bluetoothradio 116 may communicate with the baseband processor 122 via theexternal device 114. Moreover, the baseband processor 122 may comprisesuitable logic, circuitry, and/or code that may enable processing of theFM data received by the FM radio Rx 118. The baseband processor 122 mayenable processing FM data to be transmitted by the FM radio Tx 121. Inthis regard, the FM radio Rx 118 and the FM radio Tx 121 may communicatewith the baseband processor 122 via the external device 114. The coupler123 may be substantially similar to the coupler 123 described withrespect to FIG. 1D, and may be enabled to select antennas fortransmission and reception, such that either antenna, or an externallycoupled antenna, may be used for transmission and/or reception. Bymonitoring external ports on the wireless device for external antennas,and optimum receive and/or transmit signal may be obtained.

FIG. 1F is a block diagram of an exemplary single chip with multipleintegrated radios that supports radio data processing, in accordancewith an embodiment of the invention. Referring to FIG. 1E, there isshown a single chip 130 that may comprise a radio portion 132 and aprocessing portion 134. The radio portion 132 may comprise a pluralityof integrated radios. For example, the radio portion 132 may comprise acell radio 140 a that supports cellular communications, a Bluetoothradio 140 b that supports Bluetooth communications, an FM receive andtransmit (Rx/Tx) radio 140 c that supports FM communications, a globalpositioning system (GPS) 140 d that supports GPS communications, and/ora wireless local area network (WLAN) 140 e that supports communicationsbased on the IEEE 802.11 standards.

The processing portion 134 may comprise at least one processor 136, amemory 138, and a peripheral transport unit (PTU) 140. The processor 136may comprise suitable logic, circuitry, and/or code that enableprocessing of data received from the radio portion 132. In this regard,each of the integrated radios may communicate with the processingportion 134. In some instances, the integrated radios may communicatewith the processing portion 134 via a common bus, for example. Thememory 138 may comprise suitable logic, circuitry, and/or code thatenable storage of data that may be utilized by the processor 136. Inthis regard, the memory 138 may store at least a portion of the datareceived by at least one of the integrated radios in the radio portion132. Moreover, the memory 138 may store at least a portion of the datathat may be transmitted by at least one of the integrated radios in theradio portion 132. The PTU 140 may comprise suitable logic, circuitry,and/or code that may enable interfacing data in the single chip 130 withother devices that may be communicatively coupled to the single chip130. In this regard, the PTU 140 may support analog and/or digitalinterfaces.

By integrating the FM radio Tx and FM radio Rx functions on a singlechip with a tunable oscillator, external ports may be monitored for theconnection of external antennas that may improve reception and/ortransmission of wireless signals.

FIG. 2 is a block diagram of an exemplary system for FM transmission andreception, in accordance with an embodiment of the invention. Referringto FIG. 2, the radio 200 may comprise two frequency synthesizers 224 aand 224 b, an FM receive (Rx) block 226, a memory 228, a processor 230,a switch network/coupler 234, an antenna block 236 and an FM transmit(Tx) block 232.

The frequency synthesizers 224 a and 224 b may comprise suitablecircuitry, logic, and/or code that may enable generation of fixed orvariable frequency signals. For example, the frequency synthesizers 224a and 224 b may each comprise one or more direct digital frequencysynthesizers, along with a clock source, such as a Bluetooth or RFIDphase-locked loop (PLL) clock generator.

The memory 228 may comprise suitable circuitry, logic, and/or code thatmay enable storing information. In this regard, the memory 228 may, forexample, enable storing information utilized for controlling and/orconfiguring the frequency synthesizers 224 a and 224 b. For example, thememory 228 may store the value of state variables that may be utilizedto control the frequency output by each of the frequency synthesizers224 a and 224 b. Additionally, the memory 228 may enable storinginformation that may be utilized to configure the FM radio Rx block 226and the FM radio Tx block 232. In this regard, the FM radio Rx block 226and/or the FM radio Tx block 232 may comprise circuitry, logic, and/orcode such as a filter, for example, that may be configured based on thedesired frequency of operation.

The processor 230 may comprise suitable circuitry, logic, and/or codethat may enable interfacing to the memory 228, the frequencysynthesizers 224 a and 224 b, the FM radio Rx block 226 and/or the FMradio Tx block 232. In this regard, the processor 230 may be enabled toexecute one or more instructions that enable reading and/or writingto/from the memory 228. Additionally, the processor 230 may be enabledto execute one or more instructions that enable providing one or morecontrol signals to the frequency synthesizer 224, the FM radio Rx block226, and/or the FM radio Tx block 232.

The FM radio Rx block 226 may comprise suitable circuitry, logic, and/orcode that may enable reception of FM signals. In this regard, the FMradio Rx block 226 may be enabled to tune to a desired channel, amplifyreceived signals, down-convert received signals, and/or demodulatereceived signals to, for example, output data and/or audio informationcomprising the channel. For example, the FM radio Rx block 226 mayutilize in-phase and quadrature local oscillator signals generated bythe frequency synthesizer 224 a to down-convert received FM signals. TheFM radio Rx block 226 may, for example, be enabled to operate over the“FM broadcast band”, or approximately 60 MHz to 130 Mhz. Signalprocessing performed by the FM radio Rx block 226 may be performed inthe analog domain or the digital domain. In this regard, the FM radio Rxblock 226 may comprise one or more analog to digital converters (ADCs)and/or digital to analog converters (DACs) which may enable processingin the analog and/or digital domain.

The FM radio Tx block 232 may comprise suitable circuitry, logic, and/orcode that may enable transmission of FM signals. In this regard, the FMradio Tx block 232 may enable frequency modulation of a carrier signalwith audio/data information. In this regard, the carrier frequency maybe generated by the clock frequency synthesizer 224 b. The FM radio Txblock 232 may also enable up-converting a modulated signal to afrequency, for example, in the “FM broadcast band”, or approximately 60MHz to 130 MHz. Additionally, the FM radio Tx block 232 may enablebuffering and/or amplifying an FM signal such that the signal may betransmitted via an antenna. In another embodiment of the invention, thefrequency synthesizer 224 a may comprise a DDFS that may be capable ofproviding FM modulation for the signal to be transmitted.

The switch network/coupler 234 may comprise suitable circuitry, logicand or code that may enable coupling the FM radio Tx block 232 and theFM radio Rx block 226 to the antenna block 236 for the transmission andreception of wireless signals. In an embodiment of the invention, theantenna block 236 may comprise a plurality of antennas. In this case,the switch network/coupler 234 may couple the FM radio Tx block 232 andthe FM radio Rx block 226 to the plurality of antennas. The plurality ofantennas may comprise internal and externally coupled antennas, or evenvarious metal components within the housing which may contain the radio200 or even metal components of the housing itself. Externally coupledantennas may comprise devices that may be utilized for other purposes,such as earphones, for example, and may improve transmission andreception of FM signals as compared to utilizing only built-in antennas.

In an exemplary operation of the system 200, one or more signalsprovided by the processor 230 may configure the system 200 to transmitand/or receive FM signals. To receive FM signals, the processor 230 mayprovide one or more control signals to frequency synthesizers 224 a and224 b in order to generate appropriate LO frequencies based on thereference signal f_(ref). In this regard, the processor may interface tothe memory 228 in order to determine the appropriate state of anycontrol signals provided to the frequency synthesizers 224 a and 224 b.In this manner, the transmit frequency and receive frequency may bedetermined independently. Accordingly, utilizing a transmit frequencydifferent from the receive frequency may enable simultaneoustransmission and reception of FM signals.

The switch network/coupler 234 may be utilized to configure the antenna236 which may comprise one or more antennas. A plurality of antennaconfigurations may be configured to determine the configuration thatresults in the strongest received signal measured. In instances where anexternal device, such as earphones, may be coupled to the wirelessdevice comprising the radio 200, it may be utilized to improve FMtransmission and reception. Since the external device may be connectedand disconnected from the device at any time, it may be advantageous toautomatically sense whether the device may be present, and configure theradio 200 to utilize the externally coupled device as an antenna whenpresent.

FIG. 3 is a block diagram illustrating an exemplary wireless deviceincorporating automatic antenna sensing and switching, in accordancewith an embodiment of the invention. Referring to FIG. 3, there is showna wireless system 300 comprising a wireless device 301 and externalantennas 303A, 303B and 303C. The wireless device 301 may compriseinternal antennas 305A and 305B, a switch network 307, an FM radiotransmit/receive (FM radio Tx/Rx) chip 309, a T/R switch 313, aninternal metal component 311 and a directional coupler 325. The FM radioTx/Rx chip 309 may comprise on-chip impedance matching blocks 315A and315B, an FM transmit (Tx) block 317, an FM receive (Rx) block 319, avoltage controller oscillator (VCO) 321, and a sense block 323.

The external antennas 303A, 303B and 303C may comprise externallycoupled antennas that each may be enabled for transmitting and receivinga signal conforming to a particular wireless protocol, such asBluetooth, RFID, and/or FM, for example. The external antennas 303A-Cmay comprise devices that may be coupled to the wireless device 301, andmay be enabled to perform other functions, such as earphones generatingaudio signals, for example, that may also serve as externally coupledantennas for transmitting and/or receiving FM signals.

The internal antennas 305A and 305B may similarly be enabled fortransmitting and receiving a signal conforming to a particular wirelessprotocol, and may be located internal to the case enclosing the wirelessdevice 301. The internal metal component 311, may comprise a metalcomponent located within and/or part of the wireless device enclosure,which when coupled to one or more of the antennas may alter thetransmit/receive characteristics, such as transmitted and/or receivedpower, for example, of the coupled one or more antennas. The number ofinternal metal components may not be limited to the number shown in FIG.3. Accordingly, the wireless device 301 may comprise any number, or evenall of the internal metal components that may affect the Tx/Rxcharacteristics of the system. The internal metal component 311 orcomponents, as well as externally coupled devices that may act asantennas, may be utilized in instances where the transmit/receivecharacteristics may be improved, such as in the transmission and/orreception of FM signals where the increased size of the antenna mayincrease signal strength.

The FM radio Tx/Rx chip 309 may comprise suitable circuitry, logicand/or code that may enable transmission and reception of FM signals.The FM radio Tx block 317 may comprise suitable circuitry, logic and/orcode that may enable transmission of FM signals via the switch network307 and selected one or more of the external antennas 303A, 303B, 303C,and/or one or more of the internal antennas 305A and 305B. In the samemanner, the FM radio Rx block 319 may comprise suitable circuitry, logicand/or code that may enable reception of FM signals over the sameselected antennas.

The on-chip impedance matching blocks 315A and 315B may comprisesuitable circuitry, logic and/or code that may enable impedance matchingof the FM radio Tx block 317 and the FM radio Rx block 319,respectively, in conjunction with the off-chip impedance matching blocks313A and 313B, with the selected one or more antennas. The on-chipimpedance matching blocks 315A and 315B may comprise selectablecapacitors of varying capacitance values, for example, such that theimpedance matching may be performed at various frequencies and/or withmultiple antenna configurations.

The VCO 321 may comprise suitable circuitry, logic and/or code that mayenable generation of a variable frequency output signal that may beutilized by the FM radio Tx block 317 and the FM radio Rx block 319 fortransmission and reception of FM signals, respectively. Additionally,the VCO 321 may be enabled to generate a test signal that may beutilized to test for the presence of an externally coupled device at oneor more external ports on the wireless device 301. The frequency of theoutput signal may be a function of an input voltage, and may becontrolled via a processor, such as the processor 230, described withrespect to FIG. 2. In another embodiment of the invention, the VCO 321may comprise a direct digital frequency synthesizer (DDFS).

The sense block 323 may comprise suitable circuitry, logic and/or codethat may enable the sensing of the magnitude of signals at the outputsof the VCO 321 and the directional coupler 313. The magnitudes may bedetermined from the magnitude of the voltages measured, such as with anenvelope detector, for example. The sense block 323 may be integrated onthe FM radio Tx/Rx chip 309, or may be external to the FM radio Tx/Rxchip 309.

The switch network 307 may comprise suitable circuitry, logic and/orcode that may enable selection of one or more of the antennas and metalcomponents that may be utilized to transmit and receive FM signals. Theswitch network may be controlled by a processor, such as the processor230, described with respect to FIG. 2. The switch network 307 may coupleone or more of the antennas comprising the external antennas 303A, 303B,303C, and/or one or more of the internal antennas 305A and 305B, as wellas one or more metal components, such as the internal metal component311, to the FM radio Tx/Rx chip 309 and/or to the directional coupler313. The internal and external antennas and internal metal component orcomponents may be connected in series or parallel to obtain multipleantenna configurations.

The switch network 307 may also comprise circuitry that may enableimpedance matching, in conjunction with the on-chip impedance matchingblocks 315A and 315B, of the FM radio Tx block 317 and/or the FM radioRx block 319 to the selected antenna configuration. The impedancematching circuitry incorporated within the switch network 307 maycomprise selectable inductors of varying inductance values, for example,such that the impedance matching may be performed at various frequenciesand/or with multiple antenna configurations. In another embodiment ofthe invention, in instances where the FM radio Tx/Rx chip may be capableof simultaneous FM transmission and reception, as described with respectto FIG. 2, the switch network 307 may be enabled to couple both the Txblock 317 and the Rx block 319 to the selected antenna configuration.

The directional coupler 313 may comprise suitable circuitry, logicand/or code that may enable passing a signal in one direction whilerejecting signals traveling in the opposite direction. The directionalcoupler 313 may receive as an input, an output signal generated by theVCO 321, and generate an output signal that may be communicated to theswitch network 307. The directional coupler 313 may allow signalstraveling in the direction from the VCO 321 toward the switch network307 and reject signals traveling in the direction from the switchnetwork 307 toward the VCO 321. Signals traveling in the direction fromthe switch network 307 toward the VCO 321 may be generated byreflections of signals due to impedance mismatch with an antennaconfiguration and/or a lack of a coupled device at a particular externalconnection port on the wireless device 301.

In operation, the FM radio Tx block 317 may be enabled to generate an FMsignal to be transmitted by the internal and/or external antennasselected by the switch network 307. The on-chip impedance matching block315A may be enabled to match the output impedance of the FM radio Tx 317to the antennas selected by the switch network 307. The switch network307 in conjunction with the on-chip impedance match block 315A may alsoprovide impedance match to the antennas selected by the switch network307.

The FM radio Rx block 319 may be enabled to receive an FM signal thatmay be received by the internal and/or external antennas selected by theswitch network 307. The on-chip impedance matching block 315B may beenabled to match the input impedance of the FM radio Rx 319 to theantennas selected by the switch network 307. The switch network 307 inconjunction with the on-chip impedance match block 315B may also provideimpedance match with the antennas selected by the switch network 307.

In an embodiment of the invention, the VCO 321 may generate a testsignal that may be utilized to test whether external devices which mayfunction as an antenna may be coupled to the wireless device 301. Thedirectional coupler 313 may allow the signal generated by the VCO 321 tobe routed to the switch network 307, while rejecting signals that may bereflected back to the directional coupler 313. The magnitude of thesignals, such as the voltage measured by an envelope detector, forexample, may be compared at the input and the output of the directionalcoupler. In an exemplary embodiment of the invention, the ratio of themagnitudes may be monitored for changes, which may indicate an externaldevice has been coupled to the wireless device 301, may be stored in amemory, such as the memory 228, described with respect to FIG. 2.

A processor, such as the processor 230, may be utilized to configure theswitch network 307 to test for the presence of an external device, whichmay comprise external antennas 303A-C. The testing for the presence ofexternally coupled devices that may function as an antenna may beperformed at random, periodically or continuously. In cases where themonitoring may be done continuously, the monitoring may be done in amanner in which the sense block 323 and/or the directional coupler 313do not cause excessive loading on the transmission and/or reception ofsignals by the FM radio Tx 317 and the FM radio Rx 319 .

FIG. 4 is a block diagram illustrating an exemplary wireless deviceantenna sensing system, in accordance with an embodiment of theinvention. Referring to FIG. 4, there is shown an FM radio Tx/Rx chip401, a directional coupler 407, a connection port 409 and an antenna411. There is also shown a test signal 413 and a reflected signal 415.The FM radio Tx/Rx chip 410 may be substantially similar to the FM radioTx/Rx chip 309, described with respect to FIG. 3, and may comprise asignal generator 403 and a sense block 405.

The FM radio Tx/Rx block 401, the sense block 403, the directionalcoupler 407 may be substantially similar to the FM radio Tx/Rx block309, the sense block 323 and the directional coupler 313 described withrespect to FIG. 3. The signal generator 403 may be substantially similarto the VCO 321, or in another embodiment of the invention may comprise aseparate signal generator. The signal generator 403 may comprise adirect digital frequency synthesizer (DDFS).

The connection port 409 may comprise suitable circuitry, logic and/orcode that may enable coupling an external device and/or antenna to thewireless device, such as the wireless device 301 described with respectto FIG. 3. The external device may comprise earphones, for example,which may also act as an antenna for the wireless device.

The antenna 411 may comprise an externally coupled antenna, or inanother embodiment of the invention may comprise a device coupled to theconnection port 409 for other purposes, such as generating an audiosignal via earphones, for example.

In operation, the signal generator 403 may generate a test signal 413,which may comprise an AC signal and may be utilized to sense whether adevice may be coupled to the connection port 409. The test signal 413may be communicated to the directional coupler 407. As the test signal413 may be traveling in the direction allowed by the directional coupler407, the test signal 413 may be allowed to pass through to theconnection port 409. In instances where there is no antenna coupled tothe connection port 409, the reflected signal may be large due the largeimpedance ratio as a result of the infinite impedance at the connectionport 409. In instances where the antenna 411 may be coupled to theconnection port 409, the reflected signal may be reduced, due to thereduced impedance at the connection port 409.

The sense block 305 may measure the magnitude of the signal at the inputto the directional coupler 407 and at the input side of the connectionport 409, which may also comprise the output terminal of the directionalcoupler 407. A reflection ratio may be defined as the ratio of thereflected signal 415 to the test signal 413, and may be proportional tothe impedance seen at the connection port 409. The open circuit ratio,where there may be no antenna coupled to the connection port 409, may bestored in memory, such as the memory 228, described with respect to FIG.2. In instances where this ratio may change, such as when the antenna411 may be connected or disconnected, for example, the sense block maymeasure a change in the reflection ratio. The change in the reflectionratio may be communicated to a processor, such as the processor 230,also described with respect to FIG. 2. In instances where it isdetermined that an antenna may be coupled to the connection port 409,processor 230 may then utilize the antenna 411 to transmit and/orreceive FM signals, for example, via a switch network, such as theswitch network 307, described with respect to FIG. 3.

FIG. 5 is a block diagram illustrating an alternative embodiment of anexternal antenna sensing system, in accordance with an embodiment of theinvention. Referring to FIG. 5, there is shown a reference clock 510, acounter 503, an on-chip tank circuit 505, external connection port 509and an external antenna 511. The on-chip tank circuit 505 may comprisean oscillator 507, an inductor L and a capacitor C. The reference clock510 and the oscillator 507 may be substantially similar to the VCO 321,described with respect to FIG. 3, and may comprise an on-chip clocksignal source. The counter 503 may comprise suitable circuitry, logicand/or code that may enable counting of the number of oscillations of asignal per given time period for determining the frequency of thesignal.

In operation, the on-chip tank circuit 505 may generate a signal at agiven frequency in instances where no external antenna, such as theexternal antenna 511, may be coupled to the external connection port509. In instances when the external antenna 511 may be coupled to theconnection port 509, the impedance may be changed, such that thefrequency of the on-chip tank circuit 505 may be changed, as detected bythe counter 503. As with the directional coupler technique describedwith respect to FIG. 3, the on-chip tank circuit 505 may be switched tothe external connection port 509 on a periodic basis or on a continualbasis utilizing a switch network, such as the switch network 307.

FIG. 6 is a flow diagram illustrating an exemplary external antennasensing process, in accordance with an embodiment of the invention.Referring to FIG. 6, in step 603, after start step 601, an external portconnection, such as the external port connection 409 may be coupled tothe directional coupler via the switch network 307. In step 605, a testsignal may be generated by the signal generator 403 and communicated tothe external port connection. The reflection ratio may be measured bythe sense block 405 in step 607. In step 609, if the reflection ratiomay be different than an open circuit reflection ratio, an antenna maybe present at the external port connection and may then be coupled tothe FM radio Tx/Rx, such as the FM radio Tx 317 and the FM radio Rx 319,followed by step 613 where FM signals may be transmitted and received.In instances where the reflection ratio may be equal to the open circuitreflection ratio, the exemplary steps may proceed directly to step 613to transmit and receive FM signals. In step 615, in instances where itmay not be desirable to shut down the FM radio Tx/Rx, the exemplarysteps may proceed to step 617 where a next external connection port maybe coupled to the directional coupler and the exemplary steps may returnto step 605 to repeat the check for an external antenna. If in step 615,it may be desirable to shut down the FM Tx/Rx, the exemplary steps mayproceed to end step 619.

In an embodiment of the invention, a method and system are disclosed fordetecting whether an external antenna 303A-C may be coupled to one ormore ports external to the wireless device 301. FM signals may betransmitted and/or received via the FM radio transmitter 317 and/or FMradio receiver 319 respectively, when the external antenna 303A-C may bedetected. The FM radio transmitter 317 may be configured fortransmitting the FM signal via the external antenna 303A-C when theexternal antenna 303A-C may be detected, and the FM radio receiver 319may be configured for receiving the FM signals via the external antenna303A-C when the external antenna 303A-C may be detected. The decouplingof one or more external antennas 303A-C from one or more of the externalports may be detected.

The FM radio transmitter 317 and FM radio receiver 319 may be configuredto transmit and/or receive FM signal, respectively, utilizing antennas305A-B and/or 311 internal to the wireless device when the decoupling ofthe one or more external antennas 303A-C may be detected. One or moretest signals may be generated within the chip 309 for detecting whetherthe external antenna 303A-C may be coupled to the one or more externalports of the wireless device 301. A reflected signal 415 resulting froma reflection of the generated one or more test signals 413 when thegenerated test signal may be communicated to the one or more externalports of the wireless device 301 may be measured and compared to aprestored value corresponding to a reflection due to an open circuit atthe one or more external ports of the wireless device. The test signalmay comprise an AC signal.

In an embodiment of the invention, a method and system are disclosed forcommunicating a test signal 413 from a signal generator 321 integratedon a chip 309 to each of one or more port connections external to thewireless device 301. A portion of the test signal that may be reflected415 by each of the external port connections may be measured andcompared to a prestored value corresponding to a reflection due to anopen circuit at each of the external port connections. In instanceswhere the reflected signal 415 indicates that an external antenna 303A-Cmay be coupled to the external port, the external port may be coupled tothe FM radio Tx/Rx 309. The signal generator 321 integrated on the chip309 may comprise a voltage controlled oscillator or a direct digitalfrequency synthesizer. The coupling of the signal generator 321 to eachof the external port connections may be performed on a periodic basis.The antenna 303A-C coupled to any of the external connections maycomprise headphones. The one or more external port connections may bedecoupled from the FM radio Tx/Rx 309 when the reflected portion 415 ofthe test signal may indicate that no antenna may be coupled to any ofthe external port connections. The test signal may comprise an AC signaland/or one or more pulses.

Certain embodiments of the invention may comprise a machine-readablestorage having stored thereon, a computer program having at least onecode section for communicating information within a network, the atleast one code section being executable by a machine for causing themachine to perform one or more of the steps described herein for autodetecting and auto switching antennas in a multi-antenna FMtransmit/receive system.

Accordingly, aspects of the invention may be realized in hardware,software, firmware or a combination thereof. The invention may berealized in a centralized fashion in at least one computer system or ina distributed fashion where different elements are spread across severalinterconnected computer systems. Any kind of computer system or otherapparatus adapted for carrying out the methods described herein issuited. A typical combination of hardware, software and firmware may bea general-purpose computer system with a computer program that, whenbeing loaded and executed, controls the computer system such that itcarries out the methods described herein.

One embodiment of the present invention may be implemented as a boardlevel product, as a single chip, application specific integrated circuit(ASIC), or with varying levels integrated on a single chip with otherportions of the system as separate components. The degree of integrationof the system will primarily be determined by speed and costconsiderations. Because of the sophisticated nature of modernprocessors, it is possible to utilize a commercially availableprocessor, which may be implemented external to an ASIC implementationof the present system. Alternatively, if the processor is available asan ASIC core or logic block, then the commercially available processormay be implemented as part of an ASIC device with various functionsimplemented as firmware.

The present invention may also be embedded in a computer programproduct, which comprises all the features enabling the implementation ofthe methods described herein, and which when loaded in a computer systemis able to carry out these methods. Computer program in the presentcontext may mean, for example, any expression, in any language, code ornotation, of a set of instructions intended to cause a system having aninformation processing capability to perform a particular functioneither directly or after either or both of the following: a) conversionto another language, code or notation; b) reproduction in a differentmaterial form. However, other meanings of computer program within theunderstanding of those skilled in the art are also contemplated by thepresent invention.

While the invention has been described with reference to certainembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted withoutdeparting from the scope of the present invention. In addition, manymodifications may be made to adapt a particular situation or material tothe teachings of the present invention without departing from its scope.Therefore, it is intended that the present invention not be limited tothe particular embodiments disclosed, but that the present inventionwill include all embodiments falling within the scope of the appendedclaims.

1.-24. (canceled)
 25. A method for wireless communication, the methodcomprising: in a wireless device comprising an FM radio transmitterand/or an FM radio receiver integrated within a chip, electronicallydetecting, via said chip, whether an external antenna is coupled to oneor more external port of said wireless device; and transmitting and/orreceiving FM signals via said FM radio transmitter and/or said FM radioreceiver respectively, when said external antenna is detected.
 26. Themethod according to claim 25, comprising configuring said FM radioreceiver for receiving said FM signals via said external antenna whensaid external antenna is detected.
 27. The method according to claim 25,comprising configuring said FM radio receiver for receiving said FMsignals via said external antenna when said external antenna isdetected.
 28. The method according to claim 25, comprising detectingwhen said external antenna is decoupled from said one or more externalports of said wireless device.
 29. The method according to claim 28,comprising configuring said FM radio transmitter for transmitting saidFM signals via one or more antennas internal to said wireless device.30. The method according to claim 28, comprising configuring said FMradio receiver for receiving said FM signals via one or more antennasinternal to said wireless device.
 31. The method according to claim 25,comprising generating from within said chip, one or more test signalsfor said detecting whether said external antenna is coupled to said oneor more external ports of said wireless device.
 32. The method accordingto claim 31, comprising measuring a reflected signal resulting fromreflection of said generated one or more test signals when saidgenerated test signal is communicated to said one or more external portsof said wireless device.
 33. The method according to claim 32,comprising comparing said measured reflected signal to a prestored valuecorresponding to a reflection due to an open circuit at said one or moreexternal ports of said wireless device.
 34. The method according toclaim 31, wherein said generated one or more test signals comprises anAC signal.
 35. The method according to claim 25, comprising detectingwhen said external antenna is connected to said one or more externalport utilizing an LC tank circuit.
 36. The method according to claim 35,comprising detecting via said LC tank circuit a change in oscillationfrequency when said external antenna is coupled to said one or moreexternal port.
 37. A system for wireless communication, the systemcomprising: a wireless device comprising an FM radio transmitter and/oran FM radio receiver integrated within a chip, said chip electronicallydetects whether an external antenna is coupled to one or more externalport of said wireless device; and said chip enables transmission and/orreception of FM signals via said FM radio transmitter and/or said FMradio receiver respectively, when said external antenna is detected. 38.The system according to claim 37, wherein said chip enablesconfiguration of said FM radio transmitter for transmitting said FMsignal via said external antenna when said external antenna is detected.39. The system according to claim 37, wherein said chip enablesconfiguration of said FM radio receiver for receiving said FM signalsvia said external antenna when said external antenna is detected. 40.The system according to claim 37, wherein said chip enables detection ofdecoupling of said external antenna from said one or more external portsof said wireless device.
 41. The system according to claim 40, whereinsaid chip enables configuration of said FM radio transmitter fortransmitting said FM signals via one or more antennas internal to saidwireless device.
 42. The system according to claim 40, wherein said chipenables configuration of said FM radio receiver for receiving said FMsignals via one or more antennas internal to said wireless device. 43.The system according to claim 37, wherein said chip enables generationof one or more test signals for said detection of whether said externalantenna is coupled to said one or more external ports of said wirelessdevice.
 44. The system according to claim 43, wherein said chip enablesmeasurement of a reflected signal resulting from reflection of saidgenerated one or more test signals when said generated test signal iscommunicated to said one or more external ports of said wireless device.45. The system according to claim 44, wherein said chip enablescomparison of said measured reflected signal to a prestored valuecorresponding to a reflection due to an open circuit at said one or moreexternal ports of said wireless device.
 46. The system according toclaim 45, wherein said generated one or more test signals comprises anAC signal.
 47. The system according to claim 37, wherein said chipenables detecting when said external antenna is connected to said one ormore external port utilizing an LC tank circuit.
 48. The systemaccording to claim 37, wherein said chip enables detecting via said LCtank circuit a change in oscillation frequency when said externalantenna is coupled to said one or more external port.